1. Field of the Invention
The present invention concerns terminal blocks used in telecommunications to connect telephone lines. It relates more particularly to the means of stowing jumper links on such blocks.
2. Description of the Prior Art
The aforementioned terminal blocks are used to cross-connect pairs of conductors of a high-capacity transport cable to pairs of conductors of lower capacity distribution cables or to cross-connect pairs of conductors of such distribution cables to pairs of conductors of subscriber lines. The cross-connections are made between two blocks in a distribution frame or sub-distribution frame box by means of jumper links.
A terminal block of this kind is described in the document FR-A-2 611 315. It comprises an insulative block in which are mounted and insulated from each other individual connection members accessible from two sides of the block. On the front (relative to its location when in use) the block has rows of projecting chimneys. The connecting members terminate individually in these chimneys and define in them front connections assigned to the jumper links. On the back of the block the connection members define corresponding rows of rear connections assigned to the cable or line conductors.
The rows of chimneys on the front are separated from each other by grooves. These grooves are provided with wire guides for the two wires of the various jumper links for each row of chimneys or front connections. The wire guides are removably mounted in the grooves. They are flat parts made to suit the dimensions of the grooves. They have channels in both sides for the jumper link wires.
These channels are open along the front edge of the wire guide when fitted into its groove. They form at the ends of this front edge two sets of partitioned individual outlets for the wires of the various jumper links. The channels on the two sides are open alternately along this front edge, substantially facing the various chimneys of the row concerned.
These wire guides constitute the means for stowing jumper links in the grooves between chimneys. They:
ensure orderly wiring, PA0 prevent the wires creating short leakage lines between chimneys, PA0 result in a neat wired block. PA0 the wire guides are extra parts of the block itself, PA0 they increase the time to wire each jumper link because:
The drawbacks of using these wire guides include:
the individual outlets from the channels at the ends of the front edge of the wire guide must be identified as well as the front connections concerned, PA1 before the jumper link wires are inserted into their channels, the two wires of each jumper link must be untwisted over a length at least equal to that of the channels which receive them or in general that of the longest channel, PA1 they create a loop at the outlet from each channel substantially facing each chimney to provide the extra length of wire needed to make the connection to the front connection in the chimney, PA1 they require the slack to be taken up when the connections have been made by pulling on the wires from the sides of the block and stowing the slack resulting at the sides in the bed of jumper links located between two rows of blocks.
In practise the wire may not slide in its wire guide channel when disconnected from its front connection. It is then difficult to obtain access to, opposes removal of the wire guide from the groove and can only be recovered using special shape pliers.
An object of the present invention is to simplify the block whilst retaining the essential advantages of the aforementioned wire guides but avoiding their drawbacks.